diff --git a/web/dashboard.py b/web/dashboard.py
index ccb21b2..54bf25a 100644
--- a/web/dashboard.py
+++ b/web/dashboard.py
@@ -278,6 +278,30 @@ class TradingDashboard:
         # Load available models for real trading
         self._load_available_models()
         
+        # Preload essential data to prevent excessive API calls during dashboard updates
+        logger.info("Preloading essential market data to cache...")
+        try:
+            # Preload key timeframes for main symbols to ensure cache is populated
+            symbols_to_preload = self.config.symbols or ['ETH/USDT', 'BTC/USDT']
+            timeframes_to_preload = ['1m', '1h', '1d']  # Skip 1s since we use WebSocket for that
+            
+            for symbol in symbols_to_preload[:2]:  # Limit to first 2 symbols
+                for timeframe in timeframes_to_preload:
+                    try:
+                        # Load data into cache (refresh=True for initial load, then cache will be used)
+                        df = self.data_provider.get_historical_data(symbol, timeframe, limit=100, refresh=True)
+                        if df is not None and not df.empty:
+                            logger.info(f"Preloaded {len(df)} {timeframe} bars for {symbol}")
+                        else:
+                            logger.warning(f"Failed to preload data for {symbol} {timeframe}")
+                    except Exception as e:
+                        logger.warning(f"Error preloading {symbol} {timeframe}: {e}")
+            
+            logger.info("Preloading completed - cache populated for frequent queries")
+            
+        except Exception as e:
+            logger.warning(f"Error during preloading: {e}")
+        
         # Create Dash app
         self.app = dash.Dash(__name__, external_stylesheets=[
             'https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/css/bootstrap.min.css',
@@ -829,7 +853,7 @@ class TradingDashboard:
                         else:
                             # Only try fresh API call if we have no data at all
                             try:
-                                fresh_data = self.data_provider.get_historical_data(symbol, '1m', limit=1, refresh=True)
+                                fresh_data = self.data_provider.get_historical_data(symbol, '1m', limit=1, refresh=False)
                                 if fresh_data is not None and not fresh_data.empty:
                                     current_price = float(fresh_data['close'].iloc[-1])
                                     data_source = "API"
@@ -4571,7 +4595,7 @@ class TradingDashboard:
                                 symbol=target_symbol,
                                 timeframe='1m',
                                 limit=50,
-                                refresh=True
+                                refresh=False  # Use cache to prevent excessive API calls
                             )
                     else:
                         # Get historical data for other timeframes
@@ -4579,7 +4603,7 @@ class TradingDashboard:
                             symbol=target_symbol,
                             timeframe=timeframe,
                             limit=50,  # Last 50 bars
-                            refresh=True
+                            refresh=False  # Use cache to prevent excessive API calls
                         )
                     
                     if df is not None and not df.empty and len(df) >= 10:
@@ -4608,7 +4632,7 @@ class TradingDashboard:
                             symbol='BTC/USDT',
                             timeframe='1m',
                             limit=50,
-                            refresh=True
+                            refresh=False  # Use cache to prevent excessive API calls
                         )
                     
                     if btc_1s_df is not None and not btc_1s_df.empty and len(btc_1s_df) >= 10: